0000000000018155

AUTHOR

Concepción Gimeno

Would Kinetic Analyses of Plasma Cytomegalovirus DNA Load Help to Reach Consensus Criteria for Triggering the Initiation of Preemptive Antiviral Therapy in Transplant Recipients?: Table 1.

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Detection of two simultaneous outbreaks of Klebsiella pneumoniae coproducing OXA-48 and NDM-1 carbapenemases in a tertiary-care hospital in Valencia, Spain

Klebsiella pneumoniae is one of the most common hospital-acquired Gram-negative pathogens. During the last decade, the emergence of strains with reduced susceptibility or resistance to carbapenems is becoming a therapeutic challenge. This study takes place after the isolation of 14 strains of carbapenem-resistant K. pneumoniae with similar susceptibility patterns and carriage of OXA-48 and NDM-1 carbapenemases genes. Fourteen patients were found to be colonized (faecal carriage) and/or infected by two different clones of carbapenemase-coproducing K. pneumoniae during a 1-year period of time. Some of the patients had shared a hospital ward and continued to be colonized several months after t…

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Identification of a large, fast-expanding HIV-1 subtype B transmission cluster among MSM in Valencia, Spain

We describe and characterize an exceptionally large HIV-1 subtype B transmission cluster occurring in the Comunidad Valenciana (CV, Spain). A total of 1806 HIV-1 protease-reverse transcriptase (PR/RT) sequences from different patients were obtained in the CV between 2004 and 2014. After subtyping and generating a phylogenetic tree with additional HIV-1 subtype B sequences, a very large transmission cluster which included almost exclusively sequences from the CV was detected (n = 143 patients). This cluster was then validated and characterized with further maximum-likelihood phylogenetic analyses and Bayesian coalescent reconstructions. With these analyses, the CV cluster was delimited to 11…

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Sequential variation in genomic RNA patterns of human rotaviruses isolated from infantile gastroenteritis

The incidence and RNA electrophoretypes of rotaviral isolates obtained from infants and young children with acute gastroenteritis were studied from October, 1985 through April, 1986. Analysis of the viral RNA was carried out by Polyacrylamide gel electrophoresis followed by silver staining. Fourteen electrophoretypes were identified. A single dominant electrophoretype was found during the first months of the rotavirus seasonal outbreak. In contrast, a large variety of RNA patterns were observed during the latter portion of the study period. Subgrouping of rotavirus isolates by a double-sandwich enzyme-linked immunosorbent assay using monoclonal-detecting antibodies showed that all strains b…

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Susceptibility of Pseudomonas aeruginosa isolates to ceftazidime is unrelated to the expression of the outer membrane protein OprC.

Previously, it has been postulated that the porin OprC facilitates the diffusion of ceftazidime through the outer membrane of Pseudomonas aeruginosa. To further investigate this claim, the outer membrane protein (OMP) profiles of 22 ceftazidime-susceptible clinical isolates were analyzed. No correlation was found between MIC values and the level of expression of OprC. Further, OprC was either undetectable or expressed in reduced amounts in 12 isolates. In contrast, OprF and OprE were present in all isolates studied. This study suggests that OprC is dispensable for the permeation of ceftazidime through the outer membrane of P. aeruginosa.

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Molecular epidemiology and drug-resistance mechanisms in carbapenem-resistant Klebsiella pneumoniae isolated in patients from a tertiary hospital in Valencia, Spain

Abstract Objectives The aim of this study has been to characterize carbapenem-resistant Klebsiella pneumoniae isolates and to determine the resistance mechanisms involved, the clonal relationship between strains and clinical and demographical data of the infected patients. Methods Clinical and demographical data from patients were collected and statistically analysed. Antimicrobial susceptibility testing was performed and resistance genes were detected both phenotypically and genotypically. Conjugation assays were performed to show horizontal transferability of resistance genes. Clonal relationship was also studied. Next-generation sequencing (NGS) was performed to obtain information regard…

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Type-Specific Antibodies to Pneumococcal Capsular Polysaccharide Acquired either Naturally or after Vaccination with Prevenar in Children with Underlying Chronic or Recurrent Lung Diseases

ABSTRACT The antibody response to capsular polysaccharides of pneumococcal serotypes 4, 6B, 9V, 14, 18C, 19F, and 23F elicited either naturally or after vaccination with Prevenar was investigated in a cohort of children ( n = 163) with underlying chronic or recurrent lung diseases at risk of developing pneumococcal pneumonia and ultimately invasive disease. Serum concentrations of serotype-specific antibodies, as measured by enzyme-linked immunosorbent assay, in unvaccinated children ( n = 88) were higher in nasopharyngeal carriers ( n = 10) than in noncarriers ( n = 78) both at baseline and during follow-up. However, the antibody levels depended on the serotype and age of the children. Dur…

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Factores predisponentes a la infección nosocomial en el ictus agudo y su influencia en la morbimortalidad

Fundamento y objetivo El ictus constituye una causa importante de mortalidad y discapacidad. El objetivo del presente estudio es identificar los factores predictores de infeccion nosocomial en la fase aguda del ictus y como esta influye en la morbimortalidad de esta enfermedad. Pacientes y metodo Se ha realizado un estudio prospectivo, observacional y longitudinal de cohortes de pacientes con ictus agudo. El ictus se diagnostico segun la definicion de la Organizacion Mundial de la Salud, actualizada por la Sociedad Espanola de Neurologia. La infeccion nosocomial se definio por los criterios de los Centers for Disease Control y los de la Sociedad Espanola de Enfermedades Infecciosas y Microb…

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Meropenem Permeation through the Outer Membrane of <i>Pseudomonas aeruginosa</i> Can Involve Pathways Other than the OprD Porin Channel

The outer membrane protein (OMP) OprD is the major channel through which carbapenems permeate the outer membrane of Pseudomonas aeruginosa. In this study, we analyzed the OMP profiles of several P. aeruginosa clinical isolates showing diminished susceptibility to imipenem while remaining susceptible to meropenem. All these isolates lacked OprD or showed a reduced expression of this porin. Susceptibility to meropenem was thus independent of the level of OprD expression, indicating that the antimicrobial could be taken up via an alternative route. The level of expression of OprC (70 kD) was also unrelated to meropenem susceptibility. Nevertheless, OMPs OprF and OprE were expressed by all isol…

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Lack of association between the kinetics of human cytomegalovirus (HCMV) glycoprotein B (gB)-specific and neutralizing serum antibodies and development or recovery from HCMV active infection in patients undergoing allogeneic stem cell transplant

The kinetics of the gB-specific and neutralizing antibody responses to human cytomegalovirus (HCMV) were analyzed in 26 allogeneic stem-cell transplant recipients who either did (n = 20) or did not (n = 6) develop asymptomatic HCMV active infection during the study period. Antibody response profiles varied widely among individuals in both groups, irrespective of whether HCMV active infection did or did not occur. Development of HCMV active infection was not preceded by a decline in functional serum antibody levels. Neither the absence nor the presence of HCMV active infection correlated with either high or low serum levels of gB-specific and neutralizing antibodies, respectively. In most pa…

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Genetic features of Multi Drug Resistant (MDR) Klebsiella pneumoniae and its Plasmids

Klebsiella pneumoniae, a major cause of both hospital and community-acquired infections, is listed by the World Health Organization as a critical priority antibiotic- resistant bacterial pathogen. With the appearance of sequencing techniques such as Next-generation Sequencing (NGS), there is the possibility to obtain the whole genome of the bacteria, getting to know all antimicrobial resistance determinants. The purpose of this study has been to apply this new technology to clinical microbiology, in order to characterize the resistome present in carbapenem-resistant K.pneumoniae strains isolated in a tertiary hospital in Valencia, Spain. A total of 234 isolates were prepared for whole-genom…

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Lack of prompt expansion of cytomegalovirus pp65 and IE-1-specific IFNγ CD8+ and CD4+ T cells is associated with rising levels of pp65 antigenemia and DNAemia during pre-emptive therapy in allogeneic hematopoietic stem cell transplant recipients

Rising levels of cytomegalovirus (CMV) DNAemia and/or pp65 antigenemia have been observed during pre-emptive ganciclovir therapy in patients undergoing allogeneic hematopoietic stem cell transplantation (allo-SCT). We assessed the incidence of this event in our series, and investigated whether its occurrence was associated with an impairment in the CMV-specific T-cell response. A total of 36 allo-SCT recipients experienced one or more episodes of active CMV infection (n=68) that were pre-emptively treated with val(ganciclovir). Rising levels of antigenemia and DNAemia, and an isolated increase in antigenemia, were observed in 39.7 and 2.9% of all episodes, respectively. Receipt of corticost…

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Concurrent detection of human herpesvirus type 6 and measles-specific IgMs during acute exanthematic human parvovirus B19 infection

A familial outbreak of human parvovirus B19 infection is described in which serological tests carried out routinely for determining the causal agent of febrile rashes of viral etiology failed to yield a definitive diagnosis. Concurrent detection of serum IgMs to parvovirus B19 and to heterologous viruses such as human herpesvirus type 6 (HHV-6) and measles virus complicated interpretation of the data. IgG avidity tests and investigation and testing for the presence of viral DNA in sera by PCR were required to confirm parvovirus B19. The study stresses the importance of avidity and PCR tests to obtain a firm diagnosis of febrile exanthematic viral diseases.

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Evaluation of a mass spectrometry and Vitek 2 combined protocol for rapid identification and susceptibility testing of Enterobacterales directly from positive blood cultures.

Abstract Objective The aim was to evaluate a rapid method which would combine identification and susceptibility testing directly from positive blood cultures for Gram-negative bacilli of the Enterobacterales. Material and methods Gram-negative rods from blood cultures were directly identified by MALDI-TOF. Samples with Enterobacterales were selected for direct antimicrobial susceptibility testing by Vitek 2. The results were compared to those obtained with our laboratory's standard method. Results MALDI-TOF directly from blood cultures identified correctly 83% of the samples. Enterobacterales (n = 68) were identified at gender and species level in 85% of blood cultures with a score >1.7. In…

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Prophylaxis of early bacterial infections after autologous peripheral blood stem cell transplantation (PBSCT): a matched-pair study comparing oral fluoroquinolones and intravenous piperacillin-tazobactam.

The safety and efficacy of early bacterial prophylaxis with piperacillin-tazobactam were prospectively evaluated in 51 autologous peripheral blood stem cell transplantation (PBSCT) recipients. The results were compared with those obtained in 51 control patients receiving oral fluoroquinolones in a retrospective matched-pair control study. Overall, 76% of the study group and 98% of the control group developed at least one febrile episode during neutropenia (P=0.002). Time from neutropenia to the first febrile episode (FFE) was significantly longer in the study group than in the control group (P=0.04). Once a febrile episode appeared, the duration of fever was significantly longer in cases th…

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Performance of an automated human immunodeficiency virus (HIV) antigen/antibody combined assay for prenatal screening for HIV infection in pregnant women

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Evidence for the formation of covalent bonds between macromolecules in the domain of the wall of Candida albicans mycelial cells

An O-glycosylated mannoprotein, after its incorporation into the wall, showed an increase in its molecular weight, due at least to its association with N-glycosidic sugar chain(s). This was shown by rendering the material soluble after partial degradation of the wall structure. At present it is unknown whether this phenomenon is due to an additional transglycosylation process or whether the partial degradation of the wall solubilizes a supramolecular structure formed between the original O-glycosylated protein which becomes linked either directly or indirectly through a protein to the N-sugar chain(s).

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Assessment of Analysis of Urinary Pneumococcal Antigen by Immunochromatography for Etiologic Diagnosis of Community-Acquired Pneumonia in Adults

ABSTRACT The limitations of conventional microbiologic methods (CMM) for etiologic diagnosis of community pneumococcal pneumonia have made faster diagnostic techniques necessary. Our aim was to evaluate the usefulness of the immunochromatography (ICT) technique for detecting urinary Streptococcus pneumoniae antigen in the etiologic diagnosis of community-acquired pneumonias (CAP). This was a prospective study on in-patients with CAP in a tertiary hospital conducted from October 2000 to March 2004. Apart from using CMM to reach an etiologic diagnosis, we determined pneumococcal antigen in concentrated urine by ICT. We also determined the urinary pneumococcal antigen (UPA) content in patients…

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Expansion of the CRF19_cpx Variant in Spain

Abstract Background HIV-1 CRF19_cpx, is a recombinant variant found almost exclusively in Cuba and recently associated to a faster AIDS onset. Infection with this variant leads to higher viral loads and levels of RANTES and CXCR4 co-receptor use. Objectives The goal of this study was to assess the presence of CRF19_cpx in the Spanish province of Valencia, given its high pathogenicity. Study design 1294 HIV-1 protease-reverse transcriptase (PR/RT) sequences were obtained in Valencia (Spain), between 2005 and 2014. After subtyping, the detected CRF19_cpx sequences were aligned with 201 CRF19_cpx and 66 subtype D sequences retrieved from LANL, and subjected to maximum-likelihood phylogenetic a…

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N-acetyl-L-cysteine (NAC) inhibit mucin synthesis and pro-inflammatory mediators in alveolar type II epithelial cells infected with influenza virus A and B and with respiratory syncytial virus (RSV).

64% of chronic obstructive pulmonary disease (COPD) exacerbations are caused by respiratory infections including influenza (strains A and B) and respiratory syncytial virus (RSV). They affect the airway epithelium increasing inflammatory and apoptosis events through mechanisms involving ROS generation, and induce the release of mucins from epithelial cells that are involved in the deterioration of the patient's health during the course of the disease. The antioxidant NAC has proved useful in the management of COPD reducing symptoms, exacerbations and accelerated lung function decline. It has been shown to inhibit influenza virus replication and to diminish the release of inflammatory and ap…

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Reconstitution of lymphocyte populations and cytomegalovirus viremia or disease after allogeneic peripheral blood stem cell transplantation

Early reconstitution of lymphoid populations was monitored by immunophenotyping in 57 allogeneic peripheral blood stem cell (allo-PBSC) transplant patients either with or without cytomegalovirus (CMV) viremia or disease. Cell counts for total lymphocytes and CD4(+) T cells above the percentile 60th at day 14 postransplant were associated significantly with CMV viremia-free survival within 120 days after transplant. Recovery of total lymphocyte, CD3(+), and CD8(+) T-cell counts proceeded at a more rapid rate in CMV viremic patients than in nonviremic patients, irrespective of whether preemptive treatment with ganciclovir had been prescribed. Significant expansion of CD8(+) and CD8(+) CD57(+)…

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Quantification of DNA in Plasma by an Automated Real-Time PCR Assay (Cytomegalovirus PCR Kit) for Surveillance of Active Cytomegalovirus Infection and Guidance of Preemptive Therapy for Allogeneic Hematopoietic Stem Cell Transplant Recipients

ABSTRACT The performance of a plasma real-time PCR (cytomegalovirus [CMV] PCR kit; Abbott Diagnostics) was compared with that of the antigenemia assay for the surveillance of active CMV infection in 42 allogeneic hematopoietic stem cell transplantation (Allo-SCT) recipients. A total of 1,156 samples were analyzed by the two assays. Concordance between the two assays was 82.2%. Plasma DNA levels correlated with the number of pp65-positive cells, particularly prior to the initiation of preemptive therapy. Fifty-seven episodes of active CMV infection were detected in 37 patients: 18 were defined solely by the PCR assay and four were defined on the basis of the antigenemia assay. Either a cutof…

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Intra- and Interinstitutional Evaluation of an Etest for Vancomycin Minimum Inhibitory Concentration Measurement inStaphylococcus aureusBlood Isolates: Figure 1.

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The molecular epidemiology of HIV-1 in the Comunidad Valenciana (Spain): analysis of transmission clusters

AbstractHIV infections are still a very serious concern for public heath worldwide. We have applied molecular evolution methods to study the HIV-1 epidemics in the Comunidad Valenciana (CV, Spain) from a public health surveillance perspective. For this, we analysed 1804 HIV-1 sequences comprising protease and reverse transcriptase (PR/RT) coding regions, sampled between 2004 and 2014. These sequences were subtyped and subjected to phylogenetic analyses in order to detect transmission clusters. In addition, univariate and multinomial comparisons were performed to detect epidemiological differences between HIV-1 subtypes, and risk groups. The HIV epidemic in the CV is dominated by subtype B i…

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